This is an excellent book and the concepts are essential for anyone with health problems. All foods have chemicals in then naturally that some people cannot metabolize. These can cause anything from mild to horrifying symptoms. When I was a child I had horrible stomach aches. I went through various medical tortures including an appendectomy with no benefit. Eventually I figured out that this was caused by eating spicy foods like pepper, garlic, onions and other vegetables considered healthy.
As an adult I started having most of the symptoms of multiple sclerosis. This included numb hands, barbershop syndrome and extreme difficulty standing and walking. It was much worse on Saturdays and I wondered if going out to eat on Friday nights was causing my problem. I figured out that the corn oil in the restaurant food was the villain and my symptoms went away. Later I found a book reporting that about 70% of MS is greatly improved by removing improper oils from the diet.
These are just two examples from my life. This book explains the problem and how to find out what foods might be problems for you. Removing the foods that poison you may be the most important health factor. Even more important than removing processed foods, eating healthy foods, exercise, posture, fresh air, sunshine or any of the other very important health principles.
Having this information is vital to people with health problems.